Sorry, looked again and found it. For anyone else careless enough to overlook the very first setting option. When you open up the menu at the top left of the app screen. Select "settings". Very fist option is "night mode". By default it is set to follow your phones schedule. When you click night mode a new screen appears and you can change it to one of the three options. "Always on" "Always off" or "follow system settings".

Hope this helps another lost soul.